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glucosidases with high glucose tolerance. β-glucosidases with K
i
up to 1400 mmol L
–1
have
been reported (Decker et al., 2000) and these could be cloned into the cellulase-producing
microorganisms to produce a more efficient enzyme mixture. The removal of sugars during
hydrolysis by ultrafiltration or by employing the simultaneous saccharification and
fermentation process (SSF), where the sugars produced during enzymatic hydrolysis are
simultaneously fermented to ethanol, have also been reported as alternatives to overcome
the problem of enzyme inhibition by the final products of carbohydrate degradation (Sun &
Cheng, 2002; Jeffries & Jin, 2000).
It has been shown that ethanol also inhibits cellulases, although less intensely when
compared to glucose (Holtzapple et al., 1990; Chen & Jin, 2006). Cellulases inhibition by
ethanol follows a noncompetitive inhibition pattern for ethanol concentrations less than 4 M
and, when the ethanol concentration is increased, the enzyme is denatured. Ethanol also
interferes with enzyme (manly cellobiohydrolases) adsorption to cellulose and modifies the
cooperative effect between cellobiohydrolases and endoglucanases (Ooshima et al., 1985;
Holtzapple et al., 1990).
During the pretreatment, the lignocellulose degradation products and hemicellulose-
derived monomeric sugars formed and released into the liquid fraction (prehydrolysate)
have also been shown to inhibit enzymes activities, since the remaining solid fraction
(amorphous cellulose and lignin) is absorbed with this liquid up to 60–90% of its total
weight. Among these degradation products we can mention organic acids (acetic acid,
formic acid, and levulinic acid), sugar degradation products (furfural from xylose and 5-
hydroxymethylfurfural – HMF – from hexoses at high temperature and pressure) and lignin

degradation products (vanillin, syringaldehyde, and 4-hydroxybenzalde-hyde) (Palmqvist
et al., 1999a; Cantarella et al., 2004). However, the inhibition of enzymatic hydrolysis by
these products has not been clearly elucidated (Jorgensen et al., 2007). It has been shown
that washing the pretreated material results in faster conversion of cellulose due to removal
of inhibitors (Tengborg et al., 2001). Ultrafiltration has also been used to remove sugars and
other small compounds that may inhibit the action of the enzymes.
Another obstacle to enzymatic hydrolysis of lignocellulose carbohydrates is the possibility
of unspecific adsorption of enzymes (both cellulases and hemicellulases) onto lignin
particles or surfaces, mainly due to hydrophobic interaction and, possibly, due to ionic-type
lignin–enzyme interaction. Actually, after almost complete hydrolysis of the cellulose
fraction in lignocellulosic material, up to 60–70% of the total enzyme added can be bound to
lignin (Lu et al., 2002). Therefore, cellulases with lower affinity for lignin could be explored
in the development of new enzymatic complexes preparations (Berlin et al., 2005; Palonen et
al., 2004).
The trouble of unspecific enzymes adsorption to lignin could be overcome by the addition of
non-ionic surfactants like Tween 20 or Tween 80. It could also improve the hydrolysis rate
so that the same degree of conversion can be obtained at lower enzyme loadings.106.
Ethylene oxide polymers such as poly(ethylene glycol) (PEG) show a similar effect and it is
advantageous due to its low cost (Kristensen et al., 2007). Besides the use of surfactants,
other methods for desorbing enzymes have been developed, such as use of alkali, urea and
buffers of varying pH (Otter et al., 1989).
As previously mentioned, recycling of the enzymes from the reaction suspension as well as
from the residual substrates is an attractive way of reducing costs for enzymatic hydrolysis
(Qi et al., 2011). The addition of fresh substrate could recover free cellulases in bulk solution
Agroindustrial Wastes as Substrates for Microbial
Enzymes Production and Source of Sugar for Bioethanol Production

343
by adsorption, due to the high affinity of these enzymes for cellulose (Castanon & Wilke,
1980). The new material retaining up to 85% of the enzyme activity free solution could then

be separated and hydrolyzed in fresh media eventually with supplementation of more
enzyme (Tu et al., 2007). Since -glucosidase does not typically bind to the cellulosic
substrate it cannot be reused and supplementation with this enzyme is required at the
beginning of each round of hydrolysis in order to avoid the buildup of cellobiose and the
subsequent end-product inhibition of cellulase (Lee etal., 1995; Tu et al., 2007).
Ultrafiltration has been cited as viable process capable of recovering all of enzyme
components (endoglucanase, exoglucanase and β-glucosidase) after complete hydrolysis of
the cellulose (Mores et al., 2001; Qi et al., 2011). Depending on the lignin content of the
substrate, only up to 50% of the cellulases can be recycled using this approach. The saving is
therefore low, taking into account recovery costs (Singh et al., 1991; Lee et al., 1995).
The denaturation or loss of enzyme activity due to mechanical shear, proteolytic activity or
low thermostability should also be considered as limiting factors for hydrolysis. Besides,
due to cellobiohydrolases processivity and strong binding to cellulose chain (by the catalytic
site) obstacles can make the enzymes halt and become unproductively bound. Summarizes
the factors that limit efficient cellulose hydrolysis (Jorgensen et al., 2007).
The range of toxic compounds generated during some types of pretreatment and hydrolysis
of lignocellulosic materials, mainly with high temperature and pressure, under acidic
conditions, can limit the rapid and efficient fermentation of the hydrolysates by the
fermenting microorganisms, such as Saccharomyces cerevisiae. The inhibiting compounds are
divided in three main groups based on origin: weak acids, furan derivatives and phenolic
compounds. As mentioned above, furfural and HMF are formed from xylose and hexoses
respectively and when they are broken down, they generate formic acid. HMF degradation
also yields levulinic acid. Besides, the partial lignin breakdown generates phenolic
compounds (Palmqvist & Han-Hagerdal, 2000).
Undissociated weak acids inhibit cell growth since they are liposoluble when undissociated
and can diffuse across the plasma membrane. In the cytosol, dissociation of the acid occurs
due to the neutral intracellular pH, thus decreasing the cytosolic pH (Pampulha &Loureiro-
Dias, 1989) and cell viability. According to Verduyn et al. (1990), when fermentation pH is
low, cell proliferation and viability are inhibited also in the absence of weak acids, due to the
increased proton gradient across the plasma membrane, resulting in an increase in the

passive proton uptake rate.
Studies have been reported that furfural is metabolized by S. cerevisiae under aerobic,
oxygen-limiting and anaerobic conditions (Taherzadeh et al., 1998; Navarro, 1994; Palmqvist
et al., 1999b). Furfural is reduced to furfuryl alcohol during fermentation, with high yields,
and the reduction increases with the increasing of inoculum size and of specific growth rate
in chemostat (Fireoved & Mutharasan, 1986) and batch cultures (Taherzadeh et al., 1998). At
high furfural concentrations (above 84 mmol.g
-1
) the reduction rate decreases in anaerobic
batch fermentation, probably due to cell death (Palmqvist et al., 1999b). Aerobic growth is
less sensible to inhibition by furfuryl alcohol in S. cerevisiae than in Pichia stipitis (Weigert et
al., 1988; Palmqvist et al., 1999b). According to Palmqvist et al. (1999a) growth is more
sensitive to furfural than is ethanol production. Indeed, at low concentrations of furfural
(approximately 29 mmol/L) there is an invrease in ethanol yield. The authors reported that
this probably occurs because the reduction of furfural to furfuryl alcohol, by NADH-
dependent yeast dehydrogenases (which regenerates NAD
+
) has a higher priority than the

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reduction of dihydroxyacetone phosphate to glycerol (which regenerates NADH). Thus the
lower carbon consumption for glycerol production leads to an increase in ethanol yield.
Cell integrity is harmed by phenolic compounds, especially those of low molecular weight,
since they affect the membrane ability to act as selective barrier and enzyme matrice
(Heipieper et al., 1994). These compounds have a considerable inhibitory effect during
the fermentation of lignocellulosic hydrolysates, by a not elucidated mechanism (Delgenes
et al., 1996).
Another obstacle for the efficient enzymatic saccharification of lignocellulosic material is

related to the cellulase recycling (turnover), since the absorption characteristics of these
enzymes on lignocellulosic substrates have not yet been completely understood. The
enzymatic degradation of cellulose is a complex process that occurs at the limit of
solid/liquid phases, where the enzymes are the mobile components. When the cellulases act
in vitro on the insoluble substrate, three processes occur simultaneously: (a) physical and
chemical changes of cellulase at the solid phase (still not solubilized); (b) primary
hydrolysis, involving the liberation of soluble intermediates from the surface of cellulose
molecules that are in reaction and (c) secondary hydrolysis, involving the hydrolysis of
soluble intermediates into others of low molecular weight and, finally, into glucose
(MOISER; LADISCH; LADISCH, 2002).
In a general way, enzymatic hydrolysis rate of the lignocellulosic material rapidly decreases,
with cellulose enzymatic degradation being characterized by a fast initial phase, followed by
a slow secondary phase, which can last until all the substrate is degradated. This has been
frequently explained by the rapid hydrolysis of the easily accessible cellulosic fraction, by
strong enzyme inhibition, especially -glucosidases, by the product and the low inactivation
of absorbed enzyme molecules (Balat et al., 2008).
Cellulose is an insoluble substrate; the adsorption of the cellulases onto the cellulose surface
is the first step in the initiation of hydrolysis. Therefore, the presence of CBMs is essential
for fast and correct docking of the cellulases on the cellulose. Removal of CBMs significantly
lowers the hydrolysis rate on cellulose (Suurnäkki et al., 2000).
7. Stratagies for second generation ethanol production
Saccharification of lignollulosic material and the conversion of sugars into ethanol may
employ different strategies, carried out simultaneously or sequentially. In all cases, the
pretreatment stage is of crucial importance to increase enzymatic conversion efficiency.
When enzymatic hydrolysis and alcoholic fermentation are carried out separately, the
process is known as Separate (or Sequencial) Hydrolysis and Fermentation (SHF). In this
case, the enzymatic hydrolysis of the carbohydrates and the subsequent fermentation
of hexoses and pentoses are carried out in distinct reactors and they can be performed under
their optimum conditions, which is an advantage of this strategy. However, SHF leads to the
accumulation of the glucose derived from the hydrolysis of cellulose that can inhibit

cellulases, affecting the reaction rates and yields. Besides, part of glucose is adsorbed in
the solid residual material, lowering the sugar conversion (Soccol et al., 2010; Olofsson et
al., 2008).
Enzymatic hydrolysis and sugar fermentation can run together, in a same reactor, as
Simultaneous Saccharification and Fermentation (SSF), is faster and presents a low cost
process since only one reactor is necessary and the glucose formed is simultaneously
Agroindustrial Wastes as Substrates for Microbial
Enzymes Production and Source of Sugar for Bioethanol Production

345
fermented to ethanol, which also avoid the problem of product inhibition associated with
enzymes. The risk of contamination is lower due to the presence of ethanol, the anaerobic
conditions and the continuous withdrawal of glucose. Pentoses fermentation can be
performed in a separate reactor. One disadvantage of this strategy is relates to the different
optimum temperature for enzymatic hydrolysis (45–50
o
C) and alcoholic fermentation (28–
35 °C) (Soccol et al., 2010).
The process called Simultaneous Saccharification and Co Fermentation SSCF, pentoses and
hexoses conversion are carried out in the same reactor (Castro; Pereira Jr, 2010). Finally, in
the Consolidated BioProcessing (CBP) a single microbial community produced all the
required enzymes and converts sugars into ethanol in a single reactor (Lynd, 1996),
lowering overall costs. Studies suggest that CBP may be feasible and the researches have
focused on the development of new microorganisms adapted to this process, which has
been a key challenge (Lynd et al., 2002).
8. Conclusions
The search for “clean technologies”, using alternative feedstocks, in order to obtain
products of industrial interest, save energy and reduce effluent production is
economically advantageous and has been encouraged by environmental issues during the
last years. Researches dealing with the use of lignocellulosic wastes in bioprocesses,

specially for microorganisms cultivation and cellulases, xylanases, ligninases and other
enzymes production, stand out. These enzymes have potential for various
biotechnological applications and in recent years special attention has been given to the
destructuring, hydrolysis and saccharification of lignocellulosic material in order to
obtain fermentable sugars that can be converted into second generation ethanol by
fermenting microorganisms. However, for an efficient conversion of lignocellulosic
materials into products of industrial interest, some bottlenecks must be overcome. The
search for microbial strains suitable for cultivation in large scale, producing enzymes with
characteristics appropriate to the biotechnological processes to which they are intended is
of great importance.
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18
Are WEEE in Control?
Rethinking Strategies for Managing
Waste Electrical and Electronic Equipment
Francis O. Ongondo and Ian D. Williams
Faculty of Engineering and the Environment, University of Southampton
United Kingdom
1. Introduction
Electrical and electronic equipment (EEE) that has come to its end-of-life (EoL) either by
ceasing to function or ceasing to be of any value to its owners is commonly referred to as e-
waste (Widmer et al., 2005). In the European Union (EU), these wastes are referred to as
waste electrical and electronic equipment (WEEE). This chapter discusses two key themes
critical to understanding and tackling the challenge posed by WEEE, namely: (i) four key
issues that make WEEE a priority waste stream; and (ii) WEEE management practices in
various countries and regions. Drawing on a comprehensive literature review and four case
studies, we critically analyse and discuss the factors that influence the generation, collection
and disposal of WEEE, specifically addressing the spatial and temporal interactions of these
factors before an alternative approach to conceptualising and managing WEEE is proposed.
2. Importance of WEEE
Four key global issues make WEEE a priority waste stream, specifically: global quantities of
WEEE; resource impacts; potential health and environmental impacts; and ethical concerns.
2.1 Global quantities of WEEE
The rate of discarded EEE is growing at an alarming rate, especially in OECD countries
where markets are inundated with huge quantities of new electronic goods. As one of the

fastest growing waste streams around the world (Dalrymple et al., 2007; Darby & Obara,
2005; Davis & Herat, 2008), a phenomenal growth in the amounts of discarded WEEE has
been observed in various regions of the world (Ketai He, 2008; Nnorom & Osibanjo, 2008),
attracting the attention of various governments, environmental organisations (Greenpeace,
n.d.) and the scientific community. Increasingly short product lifecycles and rapidly
advancing technology have led to huge volumes of relatively new electronic goods being
discarded (Goosey, 2004). Although there is a paucity of reliable data, estimates place the
amount of WEEE generated globally between 20-50 million tonnes annually (Greenpeace,
n.d.; Ketai et al., 2008) although a recent estimate suggests ~40 million tonnes of WEEE are
generated annually (Schluep et al., 2009). However, we believe this figure is highly unlikely
(see Ongondo et al., 2011a) and almost certainly too low. Such large quantities of WEEE

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have focused attention not only on how WEEE is handled but also on why so much of it is
generated and ways in which it can be prevented.
2.2 Resource impacts
WEEE has an enormous resource impact (Meskers & Hagelüken, 2009). Access to and
availability of a number of raw materials key to the production of EEE is increasingly
becoming important with world reserves of metals such as gold and palladium in fast
decline and becoming more expensive (See EurActiv, 2009; Meskers & Hagelüken, 2009).
Consisting of a mixture of various materials, WEEE can be regarded as a resource of
valuable metals, such as copper, aluminium and gold. When these materials are not
recovered, raw materials have to be extracted and processed afresh to make new products,
resulting in significant loss of resources (Cui & Forssberg, 2003). Insufficient EEE is
collected, part of which is exported to developing countries where it is largely not entering
official recycling systems (Meskers & Hagelüken, 2009). When WEEE is not recycled, raw
materials have to be processed to make new products resulting in a significant loss of
resources (Bains et al., 2006; Bohr, 2007). In addition to the resources that are lost when

WEEE is discarded without some form of materials recovery, a phenomenon known as
stockpiling traps resources and prevents them from re-entering the materials/resource
stream. Stockpiling, a practice especially common in the USA and various other countries,
refers to the storing/hoarding of EoL EEE by consumers despite such devices being of little
or no use to them (Li et al., 2006; Lombard & Widmer, 2005; Wagner, 2009).
2.3 Potential health and environmental impacts
When WEEE is disposed of or recycled without any controls, there are potentially negative
impacts on human health. Containing more than 1000 different substances, many of which
are highly toxic (such as lead, mercury, arsenic and cadmium), there are potentially serious
health impacts if WEEE is not disposed of properly (Widmer et al. 2005). The open burning
of plastics, widespread general dumping, exposure to toxic solders and other malpractices
associated with improper dismantling and treatment of WEEE as observed in various
developing countries, can result in serious health consequences (Mureithi & Waema, 2008;
Natural Edge Project, 2006; Puckett et al., 2003; Widmer et al., 2005). Hence, serious concerns
have been raised with regard to the export of WEEE from developed countries for treatment
in Asian countries such as China and India, where the waste treatment operations utilized
have in some cases lead to adverse health and environmental consequences. The heavy
metals found in WEEE (such as lead) can contaminate drinking water by leaching into
groundwater from sources such as landfills (Fishbein, 2002). It is estimated that about 70%
of the heavy metals in US landfills come from WEEE (Puckett et al., 2003). The extraction of
raw materials, and the goods made from them, may also entail environmental damage
through mining, manufacturing, transport and energy use (Bains et al., 2006). Although
effective recycling has a much lower environmental footprint than primary production, it is
reported that the amount of WEEE recycled today is still low (Meskers & Hagelüken, 2009).
2.4 Ethical concerns
Two issues highlight the ethical concerns associated with WEEE. The first is the reported
incidences of child labour in informal WEEE industries/handling, especially in some parts
of Asia (Puckett et al., 2003; Shinkuma & Huong, 2009) and Africa. Secondly, the illegal
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363
shipments of WEEE from affluent countries to poorer developing countries that lack the
facilities to properly treat such wastes is becoming more prevalent (Nnorom & Osibanjo,
2008; Puckett et al., 2003). The evidence suggests a close link between ethical malpractices in
the handling of WEEE and the potential environmental and health impacts; it has been
observed that WEEE collected from illegal shipments is often handled informally with very
little regard to safety standards. Hence, prevention of illegal WEEE shipments could
alleviate (but not necessarily eradicate) negative environmental and health impacts.
3. Brief overview of WEEE management strategies in selected countries
Various strategies and practices have been adopted by a few countries and regions to
handle, regulate and prevent WEEE as a response to the above challenges posed by this
waste stream. Most of these have been enacted via legislation specific to WEEE. These are
briefly summarised below for selected countries.
3.1 Europe
In response to the large amounts of WEEE disposed within its borders every year, (~6.5
million tonnes), the EU enacted the so called WEEE Directive (Directive 2002/96/EC) which
its Member States (MS) were to transpose as legislation in their respective countries. The
extended producer responsibility (EPR)-based Directive obliges manufacturers to finance
the takeback of WEEE classified in 10 categories from consumers and ensure their safe
disposal. The legislation promotes individual producer responsibility (IPR), reuse, recycling
and other forms of recovery in order to reduce the disposal of WEEE. In addition, it sets
various annual targets for the collection, reuse and recycling of WEEE. Currently, MS are
required to annually separately collect at least 4kg of household WEEE per person. Despite
these efforts, the European Commission (EC) reports that only one-third of generated WEEE
is collected and treated according to the stipulated procedures with prevalent exports to
developing countries (Commission of the European Communities [CEC], 2008; Dalrymple et
al., 2007; European Union, 2003).
3.2 Asia
Rapid economic growth in Asia has led to an increase in the quantities of WEEE generated

in the region. Most of the WEEE generated from other parts of the world end up in Asian
countries, especially in China (receives ~90%). There is no commonly agreed political
strategy for managing WEEE in the region. However, various countries have or are in the
process of ratifying WEEE specific legislation. To cope with the alarmingly large quantities
of EoL products it receives and the attendant spontaneous illegal/informal and in some
cases (potentially) harmful handling and treatment of WEEE within the country, China has
recently legislated measures to cope with WEEE. Stockpiling of WEEE also occurs since
people rarely dispose of their used EEE due to the perception that goods retain a residual
value which might have future uses (Ketai et al., 2008; Li et al., 2006; Terazono, Murakami,
et al., 2006; Y. Wang et al., 2009; Xinhua News Agency, 2010). Japan has legislation designed
to tackle their 5 largest sources of WEEE: Televisions (TV); refrigerators; washing machines;
clothes dryers; and air conditioning units. Specific recovery targets for reuse and recycling
are stipulated by the legislation referred to as the home appliance recycling law (HARL). In
addition, the law requires consumers to pay a recycling fee at the time of disposal (Aizawa
et al., 2008; Zhang & Kimura, 2006).

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3.3 Africa
African countries still lag behind when it comes to enacting legislation to deal with WEEE.
This is despite well documented evidence showing that certain African countries have been
the recipients of WEEE illegally exported from various affluent nations. It has been observed
that informal collection, dismantling and recycling of WEEE is beginning to take shape in
several countries such as Nigeria, Ghana and Kenya. However, the absence of infrastructure
and appropriate collection and recycling services for WEEE is still a major challenge in
addition to scarcity of data on amounts of WEEE generated. In South Africa, there is both
informal and formal WEEE recycling with noticeable levels of recycling taking place (BAN,
2005; Dittke et al., 2008; Lombard & Widmer, 2005; Nnorom & Osibanjo, 2008; Rochat &
Laissaoui, 2008).

3.4 North America
Both the USA and Canada lack WEEE specific federal legislation. However, a number of
states in the USA have established some form of EPR regulations and takeback programmes
to deal with WEEE including Maine, the first state to mandate producer responsibility.
WEEE in the USA is mainly managed via municipal waste management services. As
previously mentioned, a lot of WEEE is stockpiled rather than returned for reuse/recycling
with ~24 million EoL computers and TVs destined for storage each year. In Canada, a
national scheme for the collection of mobile phones, smart phones and similar devices exists
although quantities of returned phones are still low (Canadian Wireless
Telecommunications Association, 2009; Kahhat et al., 2008; Wagner, 2009).
3.5 Latin-South America
It is reported that penetration of EEE in a number of Latin-South American countries is
reaching commensurate levels in industrialised countries. Formal recycling in some
countries is still at its infancy although many others lack any such facilities. There is lack of
political structure and logistical infrastructure to adequately handle WEEE. However, Brazil
is currently the frontrunner in attempts to formulate policy on WEEE with Costa Rica the
only country with specific WEEE legislation as of 2008. In Argentina, similar to countries in
other developing economies, stockpiling of obsolete and broken products is common
(Horne & Gertsakis, 2006; Silva et al., 2008).
3.6 Australia
Most of the WEEE generated in Australia is sent to landfills. In 2008, ~180 million WEEE
items were destined for landfills. Until recently, the country lacked a national policy for
dealing with WEEE. The end of 2009 saw the establishment of the National Waste Policy, a
10-year vision for resource recovery and waste management including a voluntary industry-
led (but Government-supported) scheme for recycling TVs and computers. The scheme was
scheduled to start operations in 2011, allowing householders to freely dispose of their EoL
products. (Davis & Herat, 2008; Garrett, 2009; TEC, 2008).
Table 1 summarises WEEE generation and management practices in selected countries. For
a thorough discussion on WEEE management practices in various countries see Ongondo
et al. (2011a).

It is clear from the preceding discussions that strategies to effectively deal with WEEE have
still not been perfected. Despite the efforts by various countries to deal with the challenge of

Are WEEE in Control?
Rethinking Strategies for Managing Waste Electrical and Electronic Equipment

365
Country
Generation
(tonnes/year)
Reported discarded items
Collection & treatment
routes
Germany 1.1 million (2005) Domestic WEEE
Designated collection
points, retailers takeback
UK 940K (2003) Domestic WEEE
Designated collection
points, retailers takeback
Switzerland 66,042 (2003) Diverse range of WEEE
National takeback
programmes
China
2.21 million
(2007)
Computers, printers,
refrigerators, mobile phones,
TVs
Mostly informal
collection and recycling

India 439K (2007)
Computers, printers,
refrigerators, mobile phones,
TVs
Informal and formal
Japan 860K (2005)
TVs, air conditioners, washin
g

machines, refrigerators
Collection via retailers
Nigeria 12.5K (2001-06)
Mobile phones chargers &
batteries
Informal
Kenya 7,350 (2007)
Computers, printers,
refrigerators, mobile phones,
TVs
Informal
South Africa 59.6K (2007)
Computers, printers,
refrigerators, mobile phones,
TVs
Informal and formal
Argentina 100K
Excludes white goods, TVs
and some consumer
electronics
Small number of takeback

schemes, municipal waste
services
Brazil 679K
Mobile and fixed phones, TVs,
PCs, radios, washing
machines, refrigerators and
freezers
Municipalities, recyclable
waste collectors
USA
2.25 million
(2007)
TVs, mobile phones, computer
products
Municipal waste services;
a number of voluntary
schemes
Canada 86K (2002)
Consumer equipment, kitchen
and household appliances
A number of voluntary
schemes
Australia -
Computers, TVs, mobile
phones and fluorescent lamps
Proposed national
recycling scheme from
2011; voluntary takeback
Table 1. WEEE generation and management in selected countries (compiled from Ongondo
et al., 2011a)

WEEE, a lot still needs to be done to promote, in the first instance, prevention of WEEE, as
well as reuse, recycling and safe treatment options (see Ongondo et al., 2011a). This situation
calls for a global rethink in how WEEE is managed. A number of alternative approaches to
managing WEEE have been proposed including the recast of the WEEE Directive which